[postgis-tickets] [PostGIS] #3587: lwgeom_mindistance2d slows down topology loading

[PostGIS]

#3587: lwgeom_mindistance2d slows down topology loading
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  Reporter:  strk      |      Owner:  strk
      Type:  defect    |     Status:  new
  Priority:  medium    |  Milestone:  PostGIS 2.2.3
 Component:  topology  |    Version:  2.2.x
Resolution:            |   Keywords:  performance
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Comment (by pramsey):

 My bet is on (1), as I recall a conversation w/ Martin in which is said
 his distance implementation used a sweepline implementation. He may be
 tossing all the edges into a bin and discarding many of them far more
 efficiently than we are. Most of your enhancements were around making
 multipart objects more efficient, but I think strk's examples are
 basically one huge part, right? It's possible my tree implementation would
 be as good as Martin's implementation, but it might not necessarily, as a
 sweepline could get a more consistent result than a depth-first search,
 which I'm pretty sure is what I'm getting out of my recursing on the
 trees.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/3587#comment:15>
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